linux-stable.git/include, branch v4.1.44

iscsi-target: Fix iscsi_np reset hung task during parallel delete

2017-09-10T20:36:09+00:00

[ Upstream commit 978d13d60c34818a41fc35962602bdfa5c03f214 ]

This patch fixes a bug associated with iscsit_reset_np_thread()
that can occur during parallel configfs rmdir of a single iscsi_np
used across multiple iscsi-target instances, that would result in
hung task(s) similar to below where configfs rmdir process context
was blocked indefinately waiting for iscsi_np->np_restart_comp
to finish:

[ 6726.112076] INFO: task dcp_proxy_node_:15550 blocked for more than 120 seconds.
[ 6726.119440]       Tainted: G        W  O     4.1.26-3321 #2
[ 6726.125045] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 6726.132927] dcp_proxy_node_ D ffff8803f202bc88     0 15550      1 0x00000000
[ 6726.140058]  ffff8803f202bc88 ffff88085c64d960 ffff88083b3b1ad0 ffff88087fffeb08
[ 6726.147593]  ffff8803f202c000 7fffffffffffffff ffff88083f459c28 ffff88083b3b1ad0
[ 6726.155132]  ffff88035373c100 ffff8803f202bca8 ffffffff8168ced2 ffff8803f202bcb8
[ 6726.162667] Call Trace:
[ 6726.165150]  [] schedule+0x32/0x80
[ 6726.170156]  [] schedule_timeout+0x214/0x290
[ 6726.176030]  [] ? __send_signal+0x52/0x4a0
[ 6726.181728]  [] wait_for_completion+0x96/0x100
[ 6726.187774]  [] ? wake_up_state+0x10/0x10
[ 6726.193395]  [] iscsit_reset_np_thread+0x62/0xe0 [iscsi_target_mod]
[ 6726.201278]  [] iscsit_tpg_disable_portal_group+0x96/0x190 [iscsi_target_mod]
[ 6726.210033]  [] lio_target_tpg_store_enable+0x4f/0xc0 [iscsi_target_mod]
[ 6726.218351]  [] configfs_write_file+0xaa/0x110
[ 6726.224392]  [] vfs_write+0xa4/0x1b0
[ 6726.229576]  [] SyS_write+0x41/0xb0
[ 6726.234659]  [] system_call_fastpath+0x12/0x71

It would happen because each iscsit_reset_np_thread() sets state
to ISCSI_NP_THREAD_RESET, sends SIGINT, and then blocks waiting
for completion on iscsi_np->np_restart_comp.

However, if iscsi_np was active processing a login request and
more than a single iscsit_reset_np_thread() caller to the same
iscsi_np was blocked on iscsi_np->np_restart_comp, iscsi_np
kthread process context in __iscsi_target_login_thread() would
flush pending signals and only perform a single completion of
np->np_restart_comp before going back to sleep within transport
specific iscsit_transport->iscsi_accept_np code.

To address this bug, add a iscsi_np->np_reset_count and update
__iscsi_target_login_thread() to keep completing np->np_restart_comp
until ->np_reset_count has reached zero.

Reported-by: Gary Guo 
Tested-by: Gary Guo 
Cc: Mike Christie 
Cc: Hannes Reinecke 
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger 
Signed-off-by: Sasha Levin

signal: protect SIGNAL_UNKILLABLE from unintentional clearing.

2017-09-10T20:36:07+00:00

[ Upstream commit 2d39b3cd34e6d323720d4c61bd714f5ae202c022 ]

Since commit 00cd5c37afd5 ("ptrace: permit ptracing of /sbin/init") we
can now trace init processes.  init is initially protected with
SIGNAL_UNKILLABLE which will prevent fatal signals such as SIGSTOP, but
there are a number of paths during tracing where SIGNAL_UNKILLABLE can
be implicitly cleared.

This can result in init becoming stoppable/killable after tracing.  For
example, running:

  while true; do kill -STOP 1; done &
  strace -p 1

and then stopping strace and the kill loop will result in init being
left in state TASK_STOPPED.  Sending SIGCONT to init will resume it, but
init will now respond to future SIGSTOP signals rather than ignoring
them.

Make sure that when setting SIGNAL_STOP_CONTINUED/SIGNAL_STOP_STOPPED
that we don't clear SIGNAL_UNKILLABLE.

Link: http://lkml.kernel.org/r/20170104122017.25047-1-jamie.iles@oracle.com
Signed-off-by: Jamie Iles 
Acked-by: Oleg Nesterov 
Cc: Alexander Viro 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

mm, slab: make sure that KMALLOC_MAX_SIZE will fit into MAX_ORDER

2017-09-10T20:36:06+00:00

[ Upstream commit bb1107f7c6052c863692a41f78c000db792334bf ]

Andrey Konovalov has reported the following warning triggered by the
syzkaller fuzzer.

  WARNING: CPU: 1 PID: 9935 at mm/page_alloc.c:3511 __alloc_pages_nodemask+0x159c/0x1e20
  Kernel panic - not syncing: panic_on_warn set ...
  CPU: 1 PID: 9935 Comm: syz-executor0 Not tainted 4.9.0-rc7+ #34
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
    __alloc_pages_slowpath mm/page_alloc.c:3511
    __alloc_pages_nodemask+0x159c/0x1e20 mm/page_alloc.c:3781
    alloc_pages_current+0x1c7/0x6b0 mm/mempolicy.c:2072
    alloc_pages include/linux/gfp.h:469
    kmalloc_order+0x1f/0x70 mm/slab_common.c:1015
    kmalloc_order_trace+0x1f/0x160 mm/slab_common.c:1026
    kmalloc_large include/linux/slab.h:422
    __kmalloc+0x210/0x2d0 mm/slub.c:3723
    kmalloc include/linux/slab.h:495
    ep_write_iter+0x167/0xb50 drivers/usb/gadget/legacy/inode.c:664
    new_sync_write fs/read_write.c:499
    __vfs_write+0x483/0x760 fs/read_write.c:512
    vfs_write+0x170/0x4e0 fs/read_write.c:560
    SYSC_write fs/read_write.c:607
    SyS_write+0xfb/0x230 fs/read_write.c:599
    entry_SYSCALL_64_fastpath+0x1f/0xc2

The issue is caused by a lack of size check for the request size in
ep_write_iter which should be fixed.  It, however, points to another
problem, that SLUB defines KMALLOC_MAX_SIZE too large because the its
KMALLOC_SHIFT_MAX is (MAX_ORDER + PAGE_SHIFT) which means that the
resulting page allocator request might be MAX_ORDER which is too large
(see __alloc_pages_slowpath).

The same applies to the SLOB allocator which allows even larger sizes.
Make sure that they are capped properly and never request more than
MAX_ORDER order.

Link: http://lkml.kernel.org/r/20161220130659.16461-2-mhocko@kernel.org
Signed-off-by: Michal Hocko 
Reported-by: Andrey Konovalov 
Acked-by: Christoph Lameter 
Cc: Alexei Starovoitov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

wext: handle NULL extra data in iwe_stream_add_point better

2017-09-10T20:36:05+00:00

[ Upstream commit 93be2b74279c15c2844684b1a027fdc71dd5d9bf ]

gcc-7 complains that wl3501_cs passes NULL into a function that
then uses the argument as the input for memcpy:

drivers/net/wireless/wl3501_cs.c: In function 'wl3501_get_scan':
include/net/iw_handler.h:559:3: error: argument 2 null where non-null expected [-Werror=nonnull]
   memcpy(stream + point_len, extra, iwe->u.data.length);

This works fine here because iwe->u.data.length is guaranteed to be 0
and the memcpy doesn't actually have an effect.

Making the length check explicit avoids the warning and should have
no other effect here.

Also check the pointer itself, since otherwise we get warnings
elsewhere in the code.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

sctp: fix the check for _sctp_walk_params and _sctp_walk_errors

2017-09-10T20:36:03+00:00

[ Upstream commit 6b84202c946cd3da3a8daa92c682510e9ed80321 ]

Commit b1f5bfc27a19 ("sctp: don't dereference ptr before leaving
_sctp_walk_{params, errors}()") tried to fix the issue that it
may overstep the chunk end for _sctp_walk_{params, errors} with
'chunk_end > offset(length) + sizeof(length)'.

But it introduced a side effect: When processing INIT, it verifies
the chunks with 'param.v == chunk_end' after iterating all params
by sctp_walk_params(). With the check 'chunk_end > offset(length)
+ sizeof(length)', it would return when the last param is not yet
accessed. Because the last param usually is fwdtsn supported param
whose size is 4 and 'chunk_end == offset(length) + sizeof(length)'

This is a badly issue even causing sctp couldn't process 4-shakes.
Client would always get abort when connecting to server, due to
the failure of INIT chunk verification on server.

The patch is to use 'chunk_end <= offset(length) + sizeof(length)'
instead of 'chunk_end < offset(length) + sizeof(length)' for both
_sctp_walk_params and _sctp_walk_errors.

Fixes: b1f5bfc27a19 ("sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()")
Signed-off-by: Xin Long 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

sctp: don't dereference ptr before leaving _sctp_walk_{params, errors}()

2017-09-10T20:36:03+00:00

[ Upstream commit b1f5bfc27a19f214006b9b4db7b9126df2dfdf5a ]

If the length field of the iterator (|pos.p| or |err|) is past the end
of the chunk, we shouldn't access it.

This bug has been detected by KMSAN. For the following pair of system
calls:

  socket(PF_INET6, SOCK_STREAM, 0x84 /* IPPROTO_??? */) = 3
  sendto(3, "A", 1, MSG_OOB, {sa_family=AF_INET6, sin6_port=htons(0),
         inet_pton(AF_INET6, "::1", &sin6_addr), sin6_flowinfo=0,
         sin6_scope_id=0}, 28) = 1

the tool has reported a use of uninitialized memory:

  ==================================================================
  BUG: KMSAN: use of uninitialized memory in sctp_rcv+0x17b8/0x43b0
  CPU: 1 PID: 2940 Comm: probe Not tainted 4.11.0-rc5+ #2926
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
  01/01/2011
  Call Trace:
   
   __dump_stack lib/dump_stack.c:16
   dump_stack+0x172/0x1c0 lib/dump_stack.c:52
   kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:927
   __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:469
   __sctp_rcv_init_lookup net/sctp/input.c:1074
   __sctp_rcv_lookup_harder net/sctp/input.c:1233
   __sctp_rcv_lookup net/sctp/input.c:1255
   sctp_rcv+0x17b8/0x43b0 net/sctp/input.c:170
   sctp6_rcv+0x32/0x70 net/sctp/ipv6.c:984
   ip6_input_finish+0x82f/0x1ee0 net/ipv6/ip6_input.c:279
   NF_HOOK ./include/linux/netfilter.h:257
   ip6_input+0x239/0x290 net/ipv6/ip6_input.c:322
   dst_input ./include/net/dst.h:492
   ip6_rcv_finish net/ipv6/ip6_input.c:69
   NF_HOOK ./include/linux/netfilter.h:257
   ipv6_rcv+0x1dbd/0x22e0 net/ipv6/ip6_input.c:203
   __netif_receive_skb_core+0x2f6f/0x3a20 net/core/dev.c:4208
   __netif_receive_skb net/core/dev.c:4246
   process_backlog+0x667/0xba0 net/core/dev.c:4866
   napi_poll net/core/dev.c:5268
   net_rx_action+0xc95/0x1590 net/core/dev.c:5333
   __do_softirq+0x485/0x942 kernel/softirq.c:284
   do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902
   
   do_softirq kernel/softirq.c:328
   __local_bh_enable_ip+0x25b/0x290 kernel/softirq.c:181
   local_bh_enable+0x37/0x40 ./include/linux/bottom_half.h:31
   rcu_read_unlock_bh ./include/linux/rcupdate.h:931
   ip6_finish_output2+0x19b2/0x1cf0 net/ipv6/ip6_output.c:124
   ip6_finish_output+0x764/0x970 net/ipv6/ip6_output.c:149
   NF_HOOK_COND ./include/linux/netfilter.h:246
   ip6_output+0x456/0x520 net/ipv6/ip6_output.c:163
   dst_output ./include/net/dst.h:486
   NF_HOOK ./include/linux/netfilter.h:257
   ip6_xmit+0x1841/0x1c00 net/ipv6/ip6_output.c:261
   sctp_v6_xmit+0x3b7/0x470 net/sctp/ipv6.c:225
   sctp_packet_transmit+0x38cb/0x3a20 net/sctp/output.c:632
   sctp_outq_flush+0xeb3/0x46e0 net/sctp/outqueue.c:885
   sctp_outq_uncork+0xb2/0xd0 net/sctp/outqueue.c:750
   sctp_side_effects net/sctp/sm_sideeffect.c:1773
   sctp_do_sm+0x6962/0x6ec0 net/sctp/sm_sideeffect.c:1147
   sctp_primitive_ASSOCIATE+0x12c/0x160 net/sctp/primitive.c:88
   sctp_sendmsg+0x43e5/0x4f90 net/sctp/socket.c:1954
   inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762
   sock_sendmsg_nosec net/socket.c:633
   sock_sendmsg net/socket.c:643
   SYSC_sendto+0x608/0x710 net/socket.c:1696
   SyS_sendto+0x8a/0xb0 net/socket.c:1664
   do_syscall_64+0xe6/0x130 arch/x86/entry/common.c:285
   entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:246
  RIP: 0033:0x401133
  RSP: 002b:00007fff6d99cd38 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
  RAX: ffffffffffffffda RBX: 00000000004002b0 RCX: 0000000000401133
  RDX: 0000000000000001 RSI: 0000000000494088 RDI: 0000000000000003
  RBP: 00007fff6d99cd90 R08: 00007fff6d99cd50 R09: 000000000000001c
  R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
  R13: 00000000004063d0 R14: 0000000000406460 R15: 0000000000000000
  origin:
   save_stack_trace+0x37/0x40 arch/x86/kernel/stacktrace.c:59
   kmsan_save_stack_with_flags mm/kmsan/kmsan.c:302
   kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:198
   kmsan_poison_shadow+0x6d/0xc0 mm/kmsan/kmsan.c:211
   slab_alloc_node mm/slub.c:2743
   __kmalloc_node_track_caller+0x200/0x360 mm/slub.c:4351
   __kmalloc_reserve net/core/skbuff.c:138
   __alloc_skb+0x26b/0x840 net/core/skbuff.c:231
   alloc_skb ./include/linux/skbuff.h:933
   sctp_packet_transmit+0x31e/0x3a20 net/sctp/output.c:570
   sctp_outq_flush+0xeb3/0x46e0 net/sctp/outqueue.c:885
   sctp_outq_uncork+0xb2/0xd0 net/sctp/outqueue.c:750
   sctp_side_effects net/sctp/sm_sideeffect.c:1773
   sctp_do_sm+0x6962/0x6ec0 net/sctp/sm_sideeffect.c:1147
   sctp_primitive_ASSOCIATE+0x12c/0x160 net/sctp/primitive.c:88
   sctp_sendmsg+0x43e5/0x4f90 net/sctp/socket.c:1954
   inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762
   sock_sendmsg_nosec net/socket.c:633
   sock_sendmsg net/socket.c:643
   SYSC_sendto+0x608/0x710 net/socket.c:1696
   SyS_sendto+0x8a/0xb0 net/socket.c:1664
   do_syscall_64+0xe6/0x130 arch/x86/entry/common.c:285
   return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:246
  ==================================================================

Signed-off-by: Alexander Potapenko 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

Make file credentials available to the seqfile interfaces

2017-09-10T20:35:50+00:00

[ Upstream commit 34dbbcdbf63360661ff7bda6c5f52f99ac515f92 ]

A lot of seqfile users seem to be using things like %pK that uses the
credentials of the current process, but that is actually completely
wrong for filesystem interfaces.

The unix semantics for permission checking files is to check permissions
at _open_ time, not at read or write time, and that is not just a small
detail: passing off stdin/stdout/stderr to a suid application and making
the actual IO happen in privileged context is a classic exploit
technique.

So if we want to be able to look at permissions at read time, we need to
use the file open credentials, not the current ones.  Normal file
accesses can just use "f_cred" (or any of the helper functions that do
that, like file_ns_capable()), but the seqfile interfaces do not have
any such options.

It turns out that seq_file _does_ save away the user_ns information of
the file, though.  Since user_ns is just part of the full credential
information, replace that special case with saving off the cred pointer
instead, and suddenly seq_file has all the permission information it
needs.

Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

net: phy: Do not perform software reset for Generic PHY

2017-09-10T20:35:48+00:00

[ Upstream commit 0878fff1f42c18e448ab5b8b4f6a3eb32365b5b6 ]

The Generic PHY driver is a catch-all PHY driver and it should preserve
whatever prior initialization has been done by boot loader or firmware
agents. For specific PHY device configuration it is expected that a
specialized PHY driver would take over that role.

Resetting the generic PHY was a bad idea that has lead to several
complaints and downstream workarounds e.g: in OpenWrt/LEDE so restore
the behavior prior to 87aa9f9c61ad ("net: phy: consolidate PHY
reset in phy_init_hw()").

Reported-by: Felix Fietkau 
Fixes: 87aa9f9c61ad ("net: phy: consolidate PHY reset in phy_init_hw()")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

vfio: New external user group/file match

2017-09-10T14:59:18+00:00

[ Upstream commit 5d6dee80a1e94cc284d03e06d930e60e8d3ecf7d ]

At the point where the kvm-vfio pseudo device wants to release its
vfio group reference, we can't always acquire a new reference to make
that happen.  The group can be in a state where we wouldn't allow a
new reference to be added.  This new helper function allows a caller
to match a file to a group to facilitate this.  Given a file and
group, report if they match.  Thus the caller needs to already have a
group reference to match to the file.  This allows the deletion of a
group without acquiring a new reference.

Signed-off-by: Alex Williamson 
Reviewed-by: Eric Auger 
Reviewed-by: Paolo Bonzini 
Tested-by: Eric Auger 
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin

Add "shutdown" to "struct class".

2017-07-31T17:37:55+00:00

[ Upstream commit f77af15165847406b15d8f70c382c4cb15846b2a ]

The TPM class has some common shutdown code that must be executed for
all drivers. This adds some needed functionality for that.

Signed-off-by: Josh Zimmerman 
Acked-by: Greg Kroah-Hartman 
Cc: stable@vger.kernel.org
Fixes: 74d6b3ceaa17 ("tpm: fix suspend/resume paths for TPM 2.0")
Reviewed-by: Jarkko Sakkinen 
Tested-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: James Morris 
Signed-off-by: Sasha Levin